Precious stones of the aforementioned type are known from German patent 1,557,625. Angle a between a facet of the upper part and the girdle level and angle b between a facet of the lower part and the girdle level are always selected in such a way that the diamond displays optimal brilliance seen from above. In this case, brilliance means, according to Roesch: What is a cut diamond? in: Goldschmiedezeitung [Goldsmith's Newspaper], Vol. 12, 1971, P. 39, the sum of surface shine and lower part reflection, whereby the light entering the diamond from the upper part is totally reflected on the facets of the lower part. To give a diamond as much "fire"as possible, i.e., the greatest possible opalescence, 50 plus facets were cut on the upper part in such a way that a large number of partially colored reflections pointing in various directions were obtained, contributing considerably to the appreciation of the diamond.
This consideration does not take into account the fact that a diamond is a precious, rarely occurring stone that came into being millions of years ago in the depths of the earth under extreme conditions, in a shape it kept ever since and displays today. To prepare a diamond in such a way that as a jewel, it spreads as much. fire as possible, does not, if we consider the history of the stone, do justice to its hardness, constancy and clarity as well as the esthetics of the material.